1. Field of the Invention
The present invention relates to a bus structure and method capable of attenuating digital noise affecting reception sensitivity of a mobile communication terminal.
2. Description of the Related Art
A bus structure of a mobile communication terminal connects several elements such as a mobile station modem (MSM), memory, liquid crystal display (LCD), and digital signal processor (DSP). The terminal uses the common bus for addressing memory.
FIG. 1 illustrates a conventional bus structure of a mobile communication terminal.
A MSM 1, a memory 2, and a LCD module 5 are connected to a common bus 3, for example a 8-bit or 16-bit bus structure. The MSM 1 serves as a master controller for the conventional bus structure.
The MSM 1 reads data from the memory 2, the LCD module 5, or writes data into the memory 2 by way of the common bus 3. While the MSM 1 is accessing the memory 2 for performing a read or write function, the LCD module is connected to the common bus 3. In another example, while the MSM 1 is accessing the LCD module 5, the memory 2 is connected to the common bus 3. In summary, the memory 2 and the LCD module 5 are continuously connected to the common bus 3. Upon accessing the memory 2 or the LCD module 5, a pulse signal flows into the LCD module 5 or memory 2 generating digital noise.
In the conventional common bus structure, digital noise is radiated from each element such as the LCD module 5 and the memory 2. The digital noise causes a loss of radio sensitivity of the terminal. As shown in FIG. 1, the MSM 1 and the memory 2 are separated from RF blocks and positioned at a lower portion 10 of the folder. The LCD module 5 is positioned at an upper portion 20 of the folder through a flexible printed circuit board (FPCB). The LCD module 5 is connected to the common bus 3. The LCD module 5 being farthest from the MSM 1 generates most of the radiated digital noise.
The conventional terminal having the conventional bus structure has increased digital noise decreasing radio sensitivity of the mobile communication terminal. With increased speed bus processes, digital noise would cause a serious problem to the terminal.
Therefore, there is a need for a bus structure that overcomes the above problems and provides other advantages over conventional structures.